Hosel bending features

ABSTRACT

Disclosed herein are embodiments of iron-type golf club heads that comprise internal features in the hosel and/or heel regions of the club head that facilitate changing the orientation of the hosel bore relative to the front face of the club head. In some exemplary embodiments, the body comprises a heel cavity in a hosel/heel portion of the club head that extends from a body cavity behind the front face into the hosel adjacent the bore. In other embodiments, the hosel bore comprises a groove or cavity extending below where a distal tip of a shaft is positioned. These internal hosel bending features can reduce the amount of material in the club head in a desired hosel/heel region to facilitate post-manufacturing bending of the club head in that region.

FIELD

This disclosure concerns hosel bending features for iron-type golf club head.

BACKGROUND

Golf clubs are typically manufactured with standard lie angles and loft angles. Some golfers prefer to change the standard lie angles and loft angles of their golf clubs, particularly iron-type golf clubs, by having each club head plastically bent in a post-manufacturing process. In such a bending process, it can be difficult to plastically bend the material of the club head in a desired manner without adversely affecting the shape or integrity of the hosel bore, the striking face, or other parts of the club head. In addition, advancements in materials and manufacturing processes, such as extreme heat treatments, have resulted in club heads that are stronger and harder to bend and have more sensitive surface finishes. This increases the difficulty in accurately bending a club head in a desired manner without adversely affecting the club head.

SUMMARY

Disclosed herein embodiments of iron-type golf club heads that comprise internal features in the hosel and/or heel region of the club head that facilitate changing the orientation of the hosel bore relative to the body of the club head, as well as methods of bending such club heads.

In some exemplary embodiments, an iron-type golf club head comprises a hosel, a hosel bore for receiving one end of a golf club shaft, a front face for striking a golf ball, and a heel cavity that extends within a heelward region of the club head. As used herein, the term “heelward region” shall refer to a portion of a club head that is located distal to a first plane that is tangent to a distal (tip) end of the golf club shaft (when the club head is mounted on the shaft), and that is located heelward of a vertical plane that is perpendicular to a face plane of the club head and that passes through a heelward-most point on the front face that lies within the face plane. An exemplary method of bending the club head can comprise selecting such a club head, holding the front face of the club head stationary, and applying a torque to the hosel of the club head to plastically bend the club head in a region of the heel cavity in order to change the orientation of the hosel bore relative to the front face, thereby changing the loft and/or lie angle of the club head.

The hosel bore can have a longitudinal center axis and define a hosel bore projection region that is a cylindrical region of the club head distal to the hosel bore, is centered on the center axis, and has a diameter equal to a diameter of the hosel bore. In some embodiments, the heel cavity intersects the hosel bore projection region. In some embodiments, the heel cavity also intersects with the longitudinal center axis of the hosel bore.

In some embodiments, the presence of heel cavity in the heelward region of the golf club head reduces an amount of torque that is necessary to be applied to the hosel to change a lie angle of the club head by ±4° relative to another club head that is identical except for a lack of a heel cavity. For example, the amount of torque that is necessary to be applied to the hosel is reduced by at least 9% in some embodiments.

In some embodiments, the club head has a structural cross-sectional area defined by a plane that intersects the heel cavity within the heelward region of the club head. The structural cross-sectional area includes the load and force bearing portions of the body of the club head (i.e., excluding voids, cavities, filler material, etc.) that are included in the intersecting plane. A decrease in the structural cross-sectional area of the club head due to the presence of the heel cavity, relative to another club head that is identical except for a lack of a heel cavity, reduces an amount of torque that is necessary to change a lie angle of the club head by a given amount.

In some embodiments, the club head defines a body cavity in the body behind the front face (e.g., cavity-back irons or hollow irons with an enclosed internal void), and the heel cavity extends heelward from the body cavity. In some embodiments (e.g., cavity-back irons), the body has a rear lip that extends upward from the sole portion and extends between the toe portion and the heel portion such that the rear lip covers only a lower portion of the body cavity, and the heel cavity opens into the lower portion of the body cavity.

In other embodiments, the hosel comprises a cavity positioned distal to a shaft-end location where a distal end of a shaft is positioned when the shaft is functionally coupled to the club head. The cavity provides a reduced structural cross-sectional profile in the hosel distal to the shaft-end location to facilitate bending the hosel relative to the body.

In some of these embodiments, the hosel comprises a post that projects proximally from a distal end (bottom end) of the bore and the bore comprises an annular groove extending around the post that facilitates adjustment of the orientation of the hosel relative to the body.

In other embodiments, the bore comprises a distal end portion and a tapered portion proximal to the distal end portion. The tapered portion tapers from a proximal end to a narrowest diameter at a distal end that is adjacent to the distal end portion of the bore. The distal end portion of the bore comprises a generally cylindrical void having a diameter that is greater than the narrowest diameter of the tapered portion. In some of these embodiments, the tapered portion of the bore is centered on the longitudinal axis and the distal end portion of the bore is off-center from the longitudinal axis.

In still other embodiments, the bore comprises a first tapered portion tapering from a broadest diameter at a proximal end to a narrowest diameter at a distal end, a cylindrical portion extending distally from the distal end of the first tapered portion and having a diameter about equal to the narrowest diameter of the first tapered portion, and a second tapered portion having a proximal end extending from a distal end of the cylindrical portion and a distal end forming the distal-most end of the bore, the second tapered portion narrowing in diameter from its proximal end to its distal end.

Another exemplary method can comprise manufacturing a golf club head comprising a hosel, a hosel bore for receiving one end of a golf club shaft, a front face for striking a golf ball, and a heel cavity that extends within the heelward region of the club head; and after manufacturing the club head, plastically bending the club head in a region of the heel cavity in order to change the orientation of a centerline axis of the hosel bore relative to the front face without deforming the hosel bore or the front face.

In each of these embodiments, the presence of the heel cavity in the heelward region of the golf club head can allow the head to be more easily and accurately bent in a desired manner without adversely changing the shape or integrity of other parts of the club head, including the hosel bore and the front face.

The foregoing and other objects, features, and advantages of the disclosed technology will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary embodiment of an iron-type golf club head having a cavity back.

FIG. 2 is a sectional view of the club head of FIG. 1 with a rear portion removed.

FIG. 3 is a front view of the club head of FIG. 1.

FIG. 4 is sectional view of the club head of FIG. 3, taken along line 4-4 shown in FIG. 3.

FIG. 5 is a section view of the portion of the club head shown in FIG. 4, taken along line 5-5 shown in FIG. 4.

FIG. 6 is a sectional view of a front portion of the club head of FIG. 1.

FIG. 7 is a sectional view of a rear portion of the club head of FIG. 1 that corresponds to the front portion shown in FIG. 6.

FIG. 8 is a sectional view of a front portion of the club head of FIG. 1, taken along line 8-8 shown in FIG. 4.

FIG. 9 is a partially sectional front view of another exemplary embodiment of an iron-type golf club head, showing a cross-section of its hosel bore.

FIG. 9A is an enlarged view of the bottom end of the hosel bore of FIG. 9.

FIG. 10 is a sectional heel view of the club head of FIG. 9, showing another cross-section of its hosel bore.

FIG. 11 is a partially sectional front view of yet another exemplary embodiment of an iron-type golf club head, showing a cross-section of its hosel bore.

FIG. 11A is an enlarged view of the bottom end of the hosel bore of FIG. 11.

FIG. 12 is a partially sectional heel view of the club head of FIG. 11, showing another cross-section of its hosel bore.

FIG. 13 is a partially sectional front view of a portion of still another exemplary embodiment of an iron-type golf club head, showing a cross-section of its hosel bore.

FIG. 14 is a rear view of another exemplary embodiment of an iron-type golf club head having a hollow internal region.

FIG. 15 is an end view of the club head of FIG. 14.

FIG. 16 is a sectional view of the club head of FIG. 14, taken along line 16-16 shown in FIG. 14.

FIG. 17 is a sectional view of the club head of FIG. 14, taken along line 17-17 shown in FIG. 15.

DETAILED DESCRIPTION

FIGS. 1-8 show various views of an exemplary embodiment of an iron-type golf club head 2 that is configured for improved adjustability of lie, loft and/or face angles via plastic bending. The club head 2 comprises a body 4 and a hosel 6 for coupling the club head to a shaft. The body comprises a heel portion 8 adjacent to the hosel 6, a toe portion 10 opposite from the heel portion, a sole portion 12, a topline portion 14, and a striking face portion 16 (FIG. 3) for striking golf balls.

FIG. 1 shows a perspective view of the club head 2 from the toe portion 10. FIG. 2 shows a rear view of the club head 2 with a rear portion cut away to show a heel cavity 22, which is discussed in more detail below. FIG. 3 shows the front of the club head 2, FIG. 4 shows a cross-sectional view of the club head 2 taken along line 4-4 shown in FIG. 3, and FIG. 5 shows a cross-sectional view of the portion of the club head 2 shown in FIG. 4, taken along line 5-5 shown in FIG. 4. FIGS. 4 and 5 provide additional views of the heel cavity 22. FIGS. 6 and 7 show a front portion and a rear portion, respectively, of the club head when the entire club head is divided along section line 5-5 shown in FIG. 4.

The exemplary club head 2 is a “cavity back” type club head that comprises a rear portion, or lip, 18 that extends upwardly from the sole portion 12 between the heel portion 8 and the toe portion 10 and covers a lower part of a body cavity 20 behind the face portion 16. The body cavity 20 opens rearwardly above the rear lip 18 and is defined by internal surfaces of the heel portion 8, toe portion 10, sole portion 12, topline portion 14, and face portion 16.

As shown in FIG. 2, the hosel 6 comprises a bore 24 formed within the hosel that extends to a distal end portion 26 of the bore that is adjacent to the heel portion 8 of the body 4. In some embodiments, the bore 24 is generally symmetric about a longitudinal center axis 25 of the bore and has a circular cross-sectional shape perpendicular to the center axis that varies in diameter in the direction of the center axis. The bore 24 may have a non-circular cross-sectional shape in alternative embodiments. The distal end portion 26 can taper diameter as shown, for example, in the embodiment illustrated in FIG. 2. The bore 24 is configured to receive an end of a golf club shaft, which can be secured within the bore in various manners, such as with an epoxy adhesive.

The angle that the center axis 25 of the bore makes with the horizontal ground plane when the sole 12 is resting on the ground in an address position can define the lie angle of the club head 2. The angle that a line normal to the plane of the striking face 16 makes with the flat ground when the club head 2 is in the address position can define the loft angle of the club head. The loft angle can also be determined by the relationship between the center axis 25 of the bore relative to the striking face 16. Thus, by plastically bending the hosel relative to the striking face 16 of the club head 2, the lie and loft angles of the club head can be adjusted.

In order to modify the lie angle and/or loft angle of the club head 2, it can be desirable to bend the club head in the heelward region of the club head (defined by the line 29 in FIGS. 2 and 3, which represents a vertical plane that is perpendicular to the striking face 16 and that passes through the heelward-most point on the striking face 16 that lies within a striking face plane). However, it can be undesirable to deform the shape of the hosel bore 24 itself, as this can adversely affect the attachment of the hosel 6 to the shaft. It can also be undesirable to deform the shape of the striking face 16 or shape of the body cavity 20 behind the face portion, as this can result in decreased performance in ball striking.

In an exemplary post-manufacturing bending process, the body of a club head is placed in a gripping device, such as a vice, and a bending moment is applied to the hosel until a desired change in the lie and/or loft angles is achieved. For example, the angle α in FIG. 3 illustrates an exemplary change in the lie angle of the club head 2 wherein the center axis 25 is adjusted by α to a new position 25A. In an exemplary bending process, the body 4 of the club head 2 is rigidly gripped from the plane 29 toeward, and a rigid torque rod 28 is inserted into the hosel bore 24 to apply a bending moment, as shown in FIGS. 2 and 3.

The plane 29 defines the heelward end of the striking face 16, such that the planar striking face can be gripped in a rigid manner toeward of the plane 29 and to be prevented from being deformed. In particular, the plane 29 is a vertical plane that is perpendicular to a face plane (i.e., a plane defined by the face portion 16) and that also passes through a heelward-most point on the face portion 16 that lies within the face plane. (In embodiments that include a non-planar face portion 16, the face plane is defined as a plane that is perpendicular to a line that is normal to the face portion 16 at the center of the face.) The location of the plane 29 can be defined in relation to a centerface of the striking face. In FIG. 3, the plane 29 is located a distance D₁ from the centerface of the striking face 16.

The torque rod 28 can be made of material that is more rigid than the club head such that the rod does not significantly deform under an applied torque load. The rod 28 can completely or substantially completely fill the hosel bore 24 when inserted in order to distribute the applied bending moment along the inner walls of the hosel 6 with minimal stress concentrations. Because the body 4 is gripped rigidly toeward of the plane 29, plastic deformation caused by an applied torque can be isolated in the regions of the club head that are heelward of the plane 29. In addition, because the rigid rod 28 completely fills the hosel bore 24, the shape of the hosel bore can be maintained while the club head is bent.

In the embodiment shown in FIGS. 1-8, the structural cross-sectional areas in the region between the hosel bore 24 and the plane 29 are reduced in such a way as to concentrate bending stress in that region, thereby making the hosel easier to bend in that region. An exemplary structural cross-sectional area of the club head can be defined by a plane that divides the club head into two portions with all of the bore 24 being in one of the two portions and all of the club head that is toeward of the plane 29 being in the other portion. Another exemplary structural cross-sectional area can be defined by any vertical plane (i.e., normal to the ground plane when club head is in address position) between the bore 24 and the plane 29 that divides the club head into two portions. Yet another exemplary structural cross-section area can be defined by any plane that passes through the lowest point on the top surface of the club head (shown by point 9), such as a plane parallel to the plane 29 that passes through point 9. Still another exemplary structural cross-sectional area can be defined by any plane that intersects the bore center axis 25 without intersecting the hosel bore 24 or the plane 29, such as a vertical plane that intersects the center axis 25.

In addition to reduction in structural cross-sectional area in the region between the hosel bore 24 and the plane 29, the club head 2 can also be characterized in that volume of structural material in the hosel/heel region of the club is reduced in order to make that region easier to bend. An exemplary volume of structural material can be defined by the volume of structural material of the club head that is heelward of the plane 29. Another exemplary volume of structural material can be defined as the volume of structural material within the region defined by the dashed lines 27 in FIG. 2. The dashed lines 27 represent a cylindrical bore extension region that extends from the main cylindrical portion of the bore (the portion of the bore that the lead line for the reference number 24 touches in FIG. 2) parallel to the center axis 25.

To reduce the structural cross-sectional areas and/or reduce the volume of structural material in the hosel/heel region, the club head 2 comprises a heel cavity 22. The heel cavity 22 can extend from the body cavity 20, through the heel portion 8, and to a location adjacent to the distal end portion 26 of the bore 24. The presence of the heel cavity 22 reduces the structural cross-sectional areas of the club head 2 in the heelward region between the hosel bore 24 and the plane 29. Reducing the structural cross-sectional areas in this region causes bending stress to be more concentrated in this region during a post-manufacturing bending process and reduces the amount of bending torque that is needed to be applied to the hosel to create a given amount of plastic bending in this region.

As shown in FIG. 2, a portion 23 of the heel cavity 22 can intersect the cylindrical bore extension region 27 below the bore 24, reducing the volume of structural material in the bore extension region 27. This can also reduce the amount of bending torque that is needed to be applied to the hosel to create a given amount of plastic bending in this region. Furthermore, in some embodiments, the longitudinal center axis 25 of the bore 24 can intersects the heel cavity 22, as shown in FIG. 2.

As shown in FIG. 4, the heel cavity 22 can be positioned partially or completely below the level of the rear lip 18. As shown in FIGS. 4 and 5, the heel cavity 22 can have a generally rectangular, or cuboid, void having a depth or length L₁ of from about 10 mm to about 26 mm (measured from the natural heelward end of the body cavity 20), a height H₁ of at least about 3.0 mm, and a width W₁ of at least about 3.0 mm. The heel cavity 22 can have a volume of from about 300 mm³ to about 1200 mm³ (independent of the volume of the body cavity 20). The heel cavity 22 can be slightly deeper at its upper end than its lower end, such that the heel cavity 22 projects up under the distal end portion 26 of the bore 24, as shown in FIGS. 2, 5, 6 and 7, and in some cases intersects the center axis 25. FIG. 8 shows a front portion of the club head 2 taken along section line 8-8 shown in FIG. 4, which is just slightly behind the plane of the striking face of the face portion 16.

FIG. 8 shows that, in some embodiments, a portion of the heel cavity 22 can extend forward of the plane of the striking face 16. As shown in FIG. 4, the “mouth” of the heel cavity 22, where it opens into the body cavity 20, can be rearward of the plane of the striking face, and the heel cavity can project both heelward and slightly frontward such that the end portion of the heel cavity that is adjacent to the hosel bore 24 projects forward of the plane of the striking face 16. In some embodiments, at least a portion of the region 23 of the heel cavity, which intersects the bore extension region 27 below the bore 24, can also be forward of the plane of the striking face 16.

FIGS. 14-16 show another exemplary embodiment of an iron-type club head 60 that comprises a heel cavity 66 to facilitate post-manufacturing bending. The club head 60 is a hollow iron having rear wall 62 that fully encloses an internal body cavity 64, as opposed to the cavity-back iron of FIGS. 1-8 wherein the body cavity 20 is only partially enclosed and opens rearwardly. The heel cavity 66 has a generally trapezoidal shaped mouth, as shown in FIG. 16, with a broader lower end and a narrower upper end. The heel cavity 66 also has a generally trapezoidal vertical cross-sectional shape along a plane parallel to the striking face 16, as shown in FIG. 17, with a broader mouth and a narrower end adjacent to the hosel bore. The heel cavity 66 can have a volume of from about 300 mm³ to about 1200 mm³.

With regard to both the cavity back embodiment 2, and the hollow embodiment 60, by removing structural material from the heel-hosel region of the club head beneath the bore, the structural cross-sectional areas of the club head in the region of the cavity 66 can be reduced and the bending stress can be concentrated in that region, reducing the torque needed to plastically bend the club head a given amount and making the bending process easier and more accurate. Additionally, because the heel cavity is hidden within the club head, the reduction of the structural cross-sectional area in the heel-hosel region does not result in any external changes in the shape or appearance of the club head, which can be aesthetically desirable for golfers. Furthermore, the structural material removed from the heel cavity 66 can be relocated to another location on the club, such as the sole portion and/or toe portion, to provide a lower center of gravity, increased moments of inertia, or other properties that result in enhanced ball striking performance for the club head.

FIGS. 9, 9A and 10 show an exemplary embodiment of a golf club head 30 that comprises an annular groove 32 surrounding a post 34 at a distal end of the hosel bore 24. The annular groove 32 extends distally from the tapered portion 26 of the bore and defines a cylindrical portion of the hosel material, or post, 34 that extends proximally within the groove 32. The absence of structural material in the region of the groove 32 can reduce structural cross-sectional areas of the club head along planes that intersect with the groove 32, concentrating bending stress in that region of the club head and reducing the amount of torque needed to be applied to the hosel in a bending process to change the lie and/or loft angle of the club head a given amount.

The hosel 6 can have an outer diameter D₂ (e.g., about 12-15 mm, such as about 13.6 mm) and an inner diameter D₃ (e.g., about 8-12 mm, such as about 9.6 mm) that is about equal to the diameter of the distal end of a golf club shaft. The inner diameter of the bore can decrease from D₃ proximal to the tapered portion 26 to a narrower inner diameter D₄ at the distal end of the tapered portion 26. As shown in FIG. 9A, the annular groove 32 extends distally from the distal end of the tapered portion and can have an outer diameter D₄ that is equal to the narrowest diameter of the tapered portion 26. D₄ can be less than or equal to about 9.6 mm. The inner diameter D₅ of the annular groove 32 is equal to the diameter of the post 34, and can be from about 0.5 mm to about 9.0 mm, but smaller than D₄. The depth of the groove 32 can be equal to the height of the post 34 H₂, which can range from about 0.5 mm to about 15 mm. The bottom of the groove 32 can be rounded or squared in some embodiments. In some embodiments, the groove 32 and post 34 have a circular cross-sectional shape perpendicular to the longitudinal center axis of the bore, while in other embodiments the cross-sectional shapes of the groove and post can be ovular, polygonal, or otherwise not circular. In some embodiments, the groove 32 and post 34 can be centered on and symmetric about the longitudinal center axis of the bore, while in other embodiments the groove and post can be offset from the center axis of the bore.

FIGS. 11, 11A and 12 show an exemplary embodiment of a golf club head 40 that comprises a disk-shaped cavity 42 extending from the distal end of the bore 24. The cavity 42 is positioned distal to the tapered region 26 and can comprise a generally cylindrical or puck-shaped void just distal to the tapered region 26. The absence of structural material in the region of the cavity 42 can reduce structural cross-sectional areas of the club head along planes that intersect with the cavity 42, concentrating bending stress in that region of the club head and reducing the amount of torque needed to be applied to the hosel in a bending process to change the lie and/or loft angle of the club head a given amount.

As shown in FIG. 11A, the inner diameter of the bore 24 can decrease from D₃ proximal to the tapered portion 26 to a narrower inner diameter D₄ at the distal end of the tapered portion 26. The cavity 42 extends distally from the distal end of the tapered portion 26 and can have a diameter of D₆ that is greater than the narrowest diameter D₄ of the tapered portion 26. D₄ can be up to about 9.6 mm, and D₆ up to about 14 mm. The depth H₃ of the cavity 42 can range from about 0.5 mm to about 15 mm. The volume of the cavity 42 can range from about 15 mm³ to about 2310 mm³.

In some embodiments, the cavity 42 has a circular cross-sectional shape perpendicular to the longitudinal center axis of the bore, while in other embodiments the cross-sectional shape of the cavity 42 can be non-circular. In some embodiments, the cavity 42 can be centered on and symmetric about the longitudinal center axis of the bore, while in other embodiments the cavity 42 can be offset from the center axis of the bore. For example, in some embodiments, the cavity 42 can have a radius R₁ from the center axis in the toeward direction of from about 3.0 mm to about 7.0 mm, and a different radius R₂ from the center axis in the heelward direction of from about 3.0 mm to about 7.0 mm. Desirably, the minimum radius of the cavity 42 from the center axis of the bore is at least one half of D₄.

FIG. 13 shows an exemplary embodiment of a golf club head 50 that comprises deeper hosel bore 24 having more than one tapered region near the distal end of the bore. The bore 24 of the club head 50 can comprises a proximal portion having an inner diameter D₃ (e.g., about 8-12 mm, such as about 9.6 mm) and a first tapered portion 26 that tapers from a maximal diameter at its proximal end to a minimal diameter D₄ (e.g., less than about 12 mm, such as less than about 9.6 mm) at its distal end. The bore 24 further comprises a cylindrical portion 52 distal to the first tapered portion 26 that has a diameter D₄, and a second tapered portion 54 that extends distally from the cylindrical portion 52 and tapers from a proximal end having a diameter D₄ to a distal end having a diameter D₇ that is less than D₄. The cylindrical portion 52 has a depth or height H₄ ranging from about 0.5 mm to about 8.0 mm. The second tapered portion 54 has a depth or height H₅ ranging from about 3.0 mm to about 15 mm. The second tapered portion 54 has a sloped side wall that forms an angle α with the center axis of the bore ranging from about 5° to about 75°.

When the club head 50 is coupled to a shaft, the distal end of the shaft is positioned proximal to cylindrical portion 52 and the second tapered portion 54, leaving the distal end of the bore empty to reduce the structural cross-section areas of the hosel below the distal end of the shaft. Similarly, with the club head 30 the annular groove 32 is distal to the distal end of the shaft, and with the club head 40, the cavity 42 is distal to the distal end of the shaft, thereby providing a reduced structural cross-sectional area in the hosel below the distal end of the shaft. With each of these embodiments, the reduced structural cross-sectional area in the hosel below the distal end of the shaft allows bending stress to be more concentrated in that region of the club head, thereby reducing the force needed to bend the club head and making the bending process easier and more accurate. Concentrating the bending strain in the area below the distal end of the shaft reduces any distortion of the hosel bore in the area above the distal end of the shaft and thereby reduces adverse effects on the hosel-shaft connection integrity.

Additionally, because the groove 32, cavity 42, cylindrical region 52, and second tapered region 54 are hidden within their respective club heads in the different embodiments, the reduction of the structural cross-sectional area in the hosel region does not result in any external changes in the shape or appearance of the club head, which can be aesthetically desirable for golfers. Furthermore, the additional structural material removed from the distal end of the bore can be relocated to another location on the club, such as the sole portion and/or the toe portion, to provide a lower center of gravity, increased moments of inertia, or other properties that result in enhanced ball striking performance for the club head.

Experimental Data

Table 1 below includes test data showing the amount of torque that is required to change the lie angle of various exemplary club heads by +4° in a post-manufacturing bending process where the body of the club head is held rigidly toeward of the plane 29 while a bending moment is applied to the hosel using the torque rod 28, as illustrated in FIGS. 2 and 3.

TABLE 1 Heat Heel Torque Test # Club Body Style Material Treat Cavity? [Nm] 1 4 Iron Hollow 450 st. st. H900 Yes 375 2 4 Iron Hollow 450 st. st. H900 Yes 370 3 4 Iron Hollow 450 st. st. H900 No >420 4 4 Iron Hollow 450 st. st. H900 No >420 5 6 Iron Cavity Back 17-4 st. st. H900 Yes 330 6 6 Iron Cavity Back 17-4 st. st. H900 Yes 370 7 6 Iron Cavity Back 17-4 st. st. H900 No 385 8 6 Iron Cavity Back 17-4 st. st. H900 No 385

Tests 1-4 were performed on 4-irons having the “hollow” body style of the club head 60 shown in FIGS. 14-17. Tests 1 and 2 were performed on embodiments having the heel cavity 66, whereas tests 3 and 4 were performed on embodiments that were similar to the club head 60 but without the heel cavity 66. Both of these hollow body embodiments were constructed of the same material (450 stainless steel) and heat treated in the same manner (H900). The embodiments of tests 1 and 2 that included the heel cavity 66 required an average torque of 372.5 Nm to change the lie angle +4°, whereas the embodiments of tests 3 and 4 that did not include a heel cavity required an average torque of greater than 420 Nm to change the lie angle +4°. Thus, the addition of the heel cavity 66 resulted in a greater than 11% reduction in the amount of torque required to change the lie angle +4°.

Tests 5-8 were performed on 6-irons having the cavity back body style of the club head 2 shown in FIGS. 1-8. Tests 5 and 6 were performed on embodiments having the heel cavity 22, whereas tests 7 and 8 were performed on embodiments that were similar to the club head 2 but without the heel cavity 22. Both of these cavity back embodiments were constructed of the same material (17-4 stainless steel) and heat treated in the same manner (H900). The embodiments of tests 5 and 6 that included the heel cavity 22 required an average torque of 350 Nm to change the lie angle +4°, whereas the embodiments of tests 7 and 8 that did not include a heel cavity required an average torque of 385 Nm to change the lie angle +4°. Thus, the addition of the heel cavity 22 resulted in a greater than 9% reduction in the amount of torque required to change the lie angle +4°.

GENERAL CONSIDERATIONS

For purposes of this description, certain aspects, advantages, and novel features of the embodiments of this disclosure are described herein. The disclosed methods, apparatuses, and systems should not be construed as limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed embodiments, alone and in various combinations and sub-combinations with one another. The methods, apparatuses, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed embodiments require that any one or more specific advantages be present or problems be solved.

As used herein, the terms “a”, “an” and “at least one” encompass one or more of the specified element. That is, if two of a particular element are present, one of these elements is also present and thus “an” element is present. The terms “a plurality of” and “plural” mean two or more of the specified element. As used herein, the term “and/or” used between the last two of a list of elements means any one or more of the listed elements. For example, the phrase “A, B, and/or C” means “A,” “B,” “C,” “A and B,” “A and C,” “B and C” or “A, B and C.” As used herein, the term “coupled” generally means physically coupled or linked and does not exclude the presence of intermediate elements between the coupled items absent specific contrary language.

In view of the many possible embodiments to which the principles of this disclosure may be applied, it should be recognized that the illustrated embodiments are only preferred examples and should not be taken as limiting the scope of the inventions. Rather, the scope of the invention is defined by the following claims. We therefore claim all that comes within the scope and spirit of these claims. 

We claim:
 1. A method of bending a golf club head comprising: selecting a golf club head comprising a hosel defining a hosel bore for receiving one end of a golf club shaft, a front face for striking a golf ball, a heelward region, and a heel cavity that extends within the heelward region; holding one of the front face or the hosel of the selected club head stationary; and applying a torque to the other of the front face or the hosel of the selected club head to plastically bend the club head in a region of the heel cavity in order to change the orientation of the hosel bore relative to the front face.
 2. The method of claim 1, wherein the hosel bore of the selected golf club defines a longitudinal center axis and a hosel bore projection region, the hosel bore projection region being a cylindrical region of the club head distal to the hosel bore that is centered on the center axis of the bore and has a diameter equal to a diameter of the hosel bore, and wherein the heel cavity intersects the hosel bore projection region.
 3. The method of claim 2, wherein the heel cavity intersects with the longitudinal center axis of the hosel bore.
 4. The method of claim 1, wherein the presence of the heel cavity reduces an amount of torque that is necessary to be applied to the hosel to change a lie angle of the selected club head by +4° relative to another club head that is identical expect for a lack of a heel cavity.
 5. The method of claim 4, wherein the amount of torque that is necessary to be applied to the hosel is reduced by at least 9% relative to another club head that is identical expect for a lack of a heel cavity.
 6. The method of claim 1, wherein the selected club head has a structural cross-sectional area defined by a plane that intersects the heel cavity between the front face and the hosel bore, and wherein a decrease in the structural cross-sectional area of the selected club head due to the presence of the heel cavity, relative to another club head that is identical expect for a lack of a heel cavity, reduces an amount of torque that is necessary to change a lie or loft angle of the selected club head by a given amount.
 7. The method of claim 1, wherein the selected club head is a cavity-back-type club head that comprises a rearwardly opening body cavity behind the front face, and the heel cavity extends toward the hosel from the body cavity.
 8. The method of claim 7, wherein the selected club head has a rear wall that extends upward from a sole portion and extends between a toe portion and a heel portion such that the rear lip covers only a lower portion of the body cavity, and wherein the heel cavity opens into the lower portion of the body cavity.
 9. The method of claim 1, wherein a portion of the heel cavity is forward of a plane defined by the front face.
 10. The method of claim 1, wherein the heel cavity comprises a depth in a toe-to-heel direction of at least 10 mm, a height in a sole-to-topline direction of at least 3 mm, and a width in a front-to-rear direction of at least 3 mm.
 11. The method of claim 1, wherein the heel cavity comprises a volume of from about 300 mm³ to about 1200 mm³.
 12. An iron-type golf club head comprising: a body having a front face for striking a golf ball, a heel portion, a toe portion, and a sole portion; and a hosel having a bore for receiving a distal end of a golf club shaft, the bore having a longitudinal axis that defines distal and proximal directions; wherein the hosel comprises a cavity positioned distal to a shaft-end location where a distal end of a shaft is positioned when the shaft is functionally coupled to the club head, and wherein the cavity provides a reduced structural cross-sectional profile in the hosel distal to the shaft-end location to facilitate bending the hosel relative to the body.
 13. The golf club head of claim 12, wherein the hosel comprises a post that projects proximally from a distal end of the bore and the cavity comprises an annular groove that extends around the post.
 14. The golf club head of claim 13, wherein the post and the annular groove are symmetric about the longitudinal axis.
 15. The golf club head of claim 12, wherein the bore comprises a tapered portion proximal to the cavity, the tapered portion tapering from its proximal end to a narrowest diameter at its distal end, which is adjacent to the cavity, the cavity comprising a generally cylindrical void having a diameter that is greater than the narrowest diameter of the tapered portion.
 16. The golf club head of claim 15, wherein the tapered portion is centered on the longitudinal axis and the distal end portion is off-center from the longitudinal axis.
 17. The golf club head of claim 16, wherein the distal end portion has a maximum radius from the longitudinal axis that is less than or equal to 7.0 mm and a minimum radius from the longitudinal axis that is greater than or equal to 3.0 mm.
 18. The golf club head of claim 12, wherein the bore further comprises a first tapered portion tapering from a broadest diameter at its proximal end to a narrowest diameter at its distal end, which is just proximal to the cavity, and the cavity comprises: a cylindrical portion extending distally from the distal end of the first tapered portion and having a diameter about equal to the narrowest diameter of the first tapered portion; and a second tapered portion having a proximal end extending from a distal end of the cylindrical portion and a distal end forming the distal-most end of the bore, the second tapered portion narrowing in diameter from its proximal end to its distal end.
 19. The golf club head of claim 18, wherein the second tapered portion of the bore comprises a sloped side wall forming an angle of from about 5° to about 75° with the longitudinal axis of the bore.
 20. A method comprising: manufacturing a golf club head comprising a hosel, a hosel bore for receiving one end of a golf club shaft, a front face for striking a golf ball, and a heel cavity that extends within a heelward region of the golf club head; and after manufacturing the club head, plastically bending the club head in a region of the heel cavity in order to change the orientation of the hosel bore relative to the front face without deforming the hosel bore or the front face. 